MROTEK PINE-16M, Руководство по настройке

Страница: 35 / 100

4.9 Configuration of Central Site Switching of PINE-16M
4-19
4.9 Configuration of Central Site Switching of
PINE-16M
4.9.1 VLAN configuration
An overview of Q-in-Q
The principle and operating process of Q-in-Q is as follows:
•
Data transmitted in a private network has a Tag of the private network, defined as CVLAN
Tag
•
When the data enters the backbone network of service provider, it will be given a VLAN Tag
of the public network, defined as SPVLAN Tag (or Outer Tag)
•
When the data reach the target private network, the SPVLAN Tag will be taken off
This process provides users with a simple layer-2 VPN tunnel.
The SPVLAN Tag goes behind Ethernet source MAC address and target MAC address in the data. It
contains 12 bits of SPVLAN ID, which supports 4096 VLANs, and 3 bits of SPVLAN CoS, which
supports 8 levels of services. In a network based on Q-in-Q, carriers can assign a SPVLAN ID for every
user port. As a result, all data enter the carriers’ network from the user side will be mapping to the
assigned SPVLAN ID, and the CVLAN ID of user is consequently protected.
Products with Q-in-Q have the following advantages in solutions for small-scale MAN or enterprise
networks:
•
4096x4096 VLAN IDs are provided to alleviate the problems caused by the scarce resource of
public network VLAN ID.
•
Users are able to lay out their own VLAN IDs, which will not lead to the conflict with public
network VLAN ID.
•
Provide a simply layer-2 VPN solution.
•
Users’ networks gain more independency. The original configuration of users’ networks does
not have to change as the network of service provider upgrades.
VLAN member port mode
Member
Port Mode
VLAN Member Properties
Access
√ A member port in Access mode can be assigned by user to only one VLAN.
√ Packets transferred out from an Access port of a specific VLAN has no 802.1Q tag.
√ Access ports from different VLANs can not communicate.
TUNNEL
√ A member port in TUNNEL mode can be assigned by user to only one VLAN.
√ Packets transferred out from a TUNNEL port of a specific VLAN has no 802.1Q outer
tag.
√ TUNNEL ports from different VLANs can not communicate.
√ Packets entering the VLAN through a TUNNEL port can be marked with two layers of
802.1Q tags.